What are the upper and lower limits of the shaft represented

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What are the upper and lower limits of the shaft represented by 60 f₈ ?
Use the following data :
Diameter 60 lies in the diameter step of 50-80 mm. Fundamental tolerance unit, i, in μm = 0.45 D^1/3 + 0.001 D, where D is the representative size in mm; Tolerance value for IT8 = 25i. Fundamental deviation for f shaft = –5.5 D 0.41

1. lower lim. = 59.924 mm, Upper lim. = 59.970 mm
2. lower lim. = 59.954 mm, Upper lim. = 60.000 mm
3. lower lim. = 59.970 mm, Upper lim. = 60.016 mm
4. lower limit = 60.000 mm, Upper limit = 60.046 mm

Correct Option: A

D = √50 × 80 = 63.25 mm
i = 0.45(D)^{1 / 3} + .001 D μm = 1.856 × 10^–6 m
Tolerance = 25i = 46.4 × 10^–6 m
Fundamental deviation δ = –(5.5) D^0.41 = –30.113 × 10^–6 = 0.030 mm (absolute)
High limit = Basic size – Fundametal deivation
High limit = 60 – 0.030 = 59.97
Lower limit = High limit –Tolerance
Lower limit = 59.77 – 0.0464 = 59.924mm